In recent years there have been many improvements to automobile transmissions of both the automatic and manual type including improvements to facilitate shifting through the different speeds or gears of the transmission. In competitive or racing-type vehicles these improvements are especially welcome in that they reduce or essentially eliminate lost time as the transmission changes speeds or gears.
One concern of race car drivers is the concern over missing shifts between the various drive positions of an automatic transmission in addition to the park, neutral and reverse gear positions.
Another problem facing race car drivers is inadvertent overshifting or undershifting which causes the driver to lose time in his attempt to effect the desired shift.
Numerous prior art patents disclose a shift mechanism comprising a plurality of levers for shifting a transmission. For example, U.S. patent of Peregrine, U.S. Pat. No. 2,604,797, discloses a plurality of parallel levers constrained to pivot in parallel planes and thereby activate a plurality of mutually slidable interlocking plates furnished with apertures through which the levers pass and cam surfaces which co-act with the levers to cause translation of the plates. The U.S. patent to Meli et al, U.S. Pat. No. 3,068,71 discloses a transmission shifting control mechanism comprising a plurality of push buttons which cooperate with slidable ejector plates. U.S. patent to Bonn, Jr., U.S. Pat. No. 2,100,936 discloses a transmission control having four levers, each of which causes translation of an inner tubular shaft.
Other U.S. patents disclose a shifting mechanism having multiple levers. For example, U.S. patent to Blackburn, U.S. Pat. No. 2,277,675, discloses a shifting mechanism incorporation a plurality of superimposed guide plates which activate gear shifting yokes via camming surfaces in response to translation of individual guide plates. The U.S. patent to Follis, U.S. Pat. No. 1,794,163, discloses a three-lever gear-shifting mechanism wherein three levers operate in parallel to cause activation of slidable shift rods. U.S. patent to Moulton, U.S. Pat. No. 1,818,241, discloses a release trigger mechanism on a gear shift lever which controls a locking member.